JP2002097957A - Cooling water control valve for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To open and close a cooling water passage with good responsiveness to a temperature variation of a heated portion without increasing the size of an entire device. SOLUTION: A valve body 15 is fitted to a throttle body 13, the cooling water outlet 15c of the valve body 15 is faced to a water temperature chamber 13a of the throttle body 13, and a valve element 16 and a temperature-sensitive responsive spring 17 for opening and closing the valve element 16 are stored in the valve chamber 15d of the valve body 15. Since the temperature-sensitive responsive spring 17 senses the cooling water temperature and the radiation heat of the throttle body 13 to control the opening and closing of the valve element 16, the temperature of the cooling water fed to the throttle body 13 can be properly controlled, and the throttle body 13 can be held in a steady temperature state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling water control valve for an engine that controls the flow of cooling water by opening and closing a valve body by a temperature-sensitive responsive spring.

[0002]

2. Description of the Related Art Generally, for example, an engine and its peripheral devices at a low temperature start are in a cold state, and a throttle valve provided on a throttle body or an idle speed control (ISC) valve which bypasses the throttle valve is used. Since the passing intake air adiabatically expands downstream of the throttle valve, the cold body at that time cools the throttle body, causing icing (freezing). Therefore, during warm-up operation, a part of the cooling water is introduced into the throttle body, and the throttle body is heated by the cooling water to prevent icing.

[0003] In this case, if the high-temperature cooling water is continuously supplied to the throttle body, the temperature of the throttle body increases, and the intake air passing through the throttle body is heated and volume-expanded, thereby lowering the charging efficiency. The cooling water passage is provided with a cooling water control valve for controlling the cooling water supplied to the throttle body in accordance with the cooling water temperature.

For example, a cooling water control valve disclosed in Japanese Patent Application Laid-Open No. 7-47721 has a thermo-wax built in a temperature-sensing portion for sensing the temperature of cooling water, a hermetic seal of the temperature-sensing portion, and a change in state of the thermo-wax. An elastic seal bag which expands and contracts in accordance with the above, a rod for attaching one end to the elastic seal bag, a valve body connected to the other end of the rod to open and close the cooling water passage, and the valve body in a valve closing direction. And a return spring for biasing.

[0005] In this prior art, at the time of a cold start, the thermo-wax is coagulated and contracted, so that the elastic seal bag that seals the temperature-sensitive part is drawn into the temperature-sensitive part, and one end is attached to the elastic seal bag. Recedes under the urging force of the return spring, and opens the valve body. As a result, during the warming-up operation, the cooling water flows through the cooling water control valve to the throttle body to heat the throttle body.

When the temperature of the cooling water rises and the thermowax melts and expands, the elastic seal bag presses the rod, which protrudes against the urging force of the return spring to close the valve body. As a result, the flow of the cooling water to the throttle body is cut off, the heating of the throttle body by the cooling water is prevented, and the volume expansion of the intake air passing through the throttle body is suppressed.

[0007]

However, in the cooling water control valve disclosed in the above-mentioned prior art, the temperature of the cooling water is easily detected because the temperature sensing part is disposed in the middle of the cooling water passage. However, it is difficult to directly sense the temperature of the throttle body and the temperature of the hot water chamber formed in the throttle body, and it is difficult to maintain the throttle body at a constant temperature.

Further, since the opening and closing of the valve is controlled by a rod which moves forward and backward in response to a change in the state of the wax, it is difficult to smoothly advance and retract the valve due to the sliding resistance of the rod. In some cases, causing a problem in responsiveness. That is, if the sliding resistance of the rod increases, even if the wax changes from the melt-expanded state to the solidified-shrinkage state, the rod does not follow, and the valve opening operation of the valve body is delayed.

To cope with this, it is conceivable to set a large spring constant of the return spring that urges the valve body in the valve opening direction. However, if the spring constant of the return spring is set to be large, the return spring is attached. The capacity of the thermowax for opening the valve body against the force must be increased, and there is a disadvantage that the entire cooling water control valve becomes large.

Accordingly, an object of the present invention is to provide a cooling water control valve for an engine capable of opening and closing a cooling water passage with good responsiveness to a temperature change of a heated portion without increasing the size of the entire apparatus. To provide.

[0011]

According to the first aspect of the present invention, there is provided a first engine coolant control valve according to the present invention, wherein engine coolant flows when the temperature is low and shuts off when the temperature is high. In the control valve, a cooling water inlet and a cooling water discharge port are provided at both ends of the valve body, a valve chamber is provided between the cooling water inlet and the cooling water discharge port, and a valve chamber is provided in the valve chamber from the cooling water inlet. A valve body that closes by moving against water pressure is provided, and a temperature-sensitive responsive spring for closing the valve body when the temperature is high is connected to the valve body.

In such a configuration, when the temperature of the cooling water flowing through the valve chamber of the valve body rises, the temperature-sensitive spring provided in the valve body is transformed to press the valve body to perform the valve closing operation. Further, when the temperature of the cooling water decreases, the urging force of the temperature-sensitive responsive spring attenuates, so that the valve body is pressed by the cooling water and opens with excellent responsiveness.

[0013] The second engine cooling water control valve is the first engine cooling water control valve, wherein the valve body has a shaft extending along a direction in which the cooling water flows, and a tip of the shaft. And a spoke portion radially provided on the outer periphery of the shaft portion, and a guide rib provided radially on the outer periphery of the valve portion, and a ring member is slidably disposed on the outer periphery of the spoke portion. The temperature-responsive spring is interposed between the ring member and the bottom of the valve chamber.

With such a configuration, when the temperature of the cooling water flowing through the valve chamber decreases and the urging force of the temperature-sensitive responsive spring decreases,
The valve portion opens, and the cooling water flowing from the cooling water inlet passes between the guide ribs formed on the outer periphery of the valve portion, and is supplied to the portion to be heated through the spokes radially provided on the outer periphery of the shaft portion. You.

A third engine cooling water control valve is the first engine cooling water control valve, wherein the valve element has a shaft extending in a direction in which the cooling water flows, and a tip of the shaft. And a spoke portion radially provided on the outer periphery of the shaft portion, and a circumferential guide portion provided on the outer periphery of the spoke portion, between the circumferential guide portion and the shaft portion. A communication hole is formed in the valve body, and the temperature-sensitive responsive spring is interposed between the circumferential guide portion and the bottom of the valve chamber.

With such a configuration, when the temperature of the cooling water flowing through the valve chamber decreases and the urging force of the temperature-sensitive responsive spring decreases,
The valve is opened, and the cooling water flowing from the cooling water inlet bypasses the valve, passes between spokes radially provided on the outer periphery of the shaft, and passes through the communication hole formed in the circumferential guide. It is supplied to the heating site.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 to 6 show a first embodiment of the present invention. FIG. 1 shows a schematic diagram of an engine cooling system.

1 is an engine body, 2 is a radiator, and an inflow side of a cooling water passage 5 formed in a cylinder block 3 and a cylinder head 4 of the engine body 1 is provided with a water pump through a cooling water supply line 6. 7 and
The suction side of the water pump 7 is connected to the radiator 2 via a first cooling water recovery line 8.
A thermostat valve 9 is interposed in the cooling water recovery line 8.

Further, the discharge side of the cooling water passage 5 formed in the engine body 1 is connected to the inflow side of the radiator 2 via a second cooling water recovery line 10 and at the same time, via a main bypass line 11. It is connected to a thermostat valve 9.

The thermostat valve 9 connects the radiator 2 and the main bypass line 1 to the water pump 7.
1 is selectively switched and connected in accordance with the cooling water temperature. When the cooling water temperature is low, the radiator 2 is shut off, and when the cooling water temperature is high, the main bypass line 11 is shut off.

Further, a sub-bypass line 12 is branched and connected to a discharge side of the cooling water passage 5 formed in the engine body 1, and a downstream side of the sub-bypass line 12 is connected to a suction side of the water pump 7. Have been. A throttle body 13, which is an example of a heated portion, is interposed in the sub bypass line 12, and a cooling water control valve 14A is interposed on the inflow side of the throttle body 13.

As shown in FIGS. 2 to 4, the valve body 15 of the cooling water control valve 14A has a body 15a formed substantially at the center thereof mounted on the throttle body 13, and a cooling water inlet 15b protruding outside. Is sub bypass line 1
The cooling water discharge port 15 c, which is connected to the upstream side and is immersed therein, has a hot water chamber 1 formed in the throttle body 13.
3a. This hot water chamber 13a is connected to the downstream side of the sub bypass line 12.

A valve chamber 15d is formed in the body 15a, and a valve body 16 is housed in the valve chamber 15d. A shaft portion 16a formed along the axial direction of the valve body 16
A disc-shaped valve portion 16b is formed at the upstream end of the cooling water inlet 15b, and a seat surface 15e is formed at a discharge port of the cooling water inlet 15b opposed to the valve portion 16b.

As shown in FIG. 5, guide ribs 16c are radially formed on the outer periphery of the valve portion 16b (a cross shape in the present embodiment).
The outer periphery of the guide rib 16c is slidably opposed to the inner wall of the valve chamber 15d. Further, FIG.
As shown in the figure, the spoke portion 16
d is formed radially (cross-shaped in the present embodiment).

The outer periphery of the spoke portion 16d and the valve chamber 15d
The temperature-responsive spring 17 is inserted between the inner wall and the inner wall.
A step portion 15f is formed on the substantially central inner wall of the valve chamber 15d, and a seal ring 18 as an example of a link member is slidably interposed between the step portion 15f and the valve portion 16b. The end face of the temperature-sensitive responsive spring 17 in the direction of expansion and contraction is abutted between 18 and the bottom of the valve chamber 15d.

The temperature-responsive spring 17 is a shape memory spring in the present embodiment, and performs a resilient operation when the cooling water temperature becomes higher than a predetermined transformation temperature (about 80 ° C.), and the sealing ring 18 is moved. The valve portion 16b is operated to close the valve.

Next, the operation of the present embodiment having the above configuration will be described. When the engine is in a cold state, the cooling water is in a low temperature state.
Cuts off the first cooling water recovery line 8 communicating between the radiator 2 and the water pump 7, and connects the main bypass line 11 to the water pump 7.

When the engine is started in this state, the cooling water discharged from the water pump 7 passes through the cooling water passage 5 formed in the engine body 1, is drawn into the water pump 7 via the main bypass line 11, and circulates. I do.

On the other hand, part of the cooling water discharged from the cooling water passage 5 flows through the sub bypass line 12 to the cooling water control valve 14A. When the cooling water temperature is low,
Since the temperature-sensitive responsive spring 17 provided in the cooling water control valve 14A becomes lower than the transformation temperature and the elastic force of the temperature-sensitive responsive spring 17 is attenuated, the temperature-sensitive responsive spring 17 depends on the cooling water pressure received by the seal ring 18. Retreat, at the same time, valve element 1
The valve portion 16b integrally formed at the tip of the valve 6 also receives the cooling water pressure and retreats.

As a result, as shown in FIG.
Is a seat surface 15e formed at the outlet of the cooling water inlet 15b.
And is opened. Then, the cooling water flowing into the valve chamber 15d from the cooling water inlet 15b flows from the gap between the guide ribs 16c formed on the outer periphery of the valve portion 16b to the spoke portion 16d formed on the outer periphery of the shaft portion 16a. Of the throttle body 13 which flows toward the cooling water discharge port 15c through the void portion of the throttle body 13 and faces the cooling water discharge port 15c.
The icing (freezing) of the throttle body 13 is prevented by flowing out into the hot water chamber 13a and circulating through the hot water chamber 13a.

Thereafter, the temperature of the cooling water rises, and the temperature-responsive spring 17 is heated by the high-temperature cooling water or by the radiant heat of the throttle body 13 transmitted through the body 15a of the valve body 15 to transform. When the temperature reaches, as shown in FIG. 4, the temperature-responsive spring 17 performs a transformation operation, and presses the valve portion 16 b of the valve body 16 via the seal ring 18,
The valve portion 16b is brought into close contact with the seat surface 15e to shut off the supply of the cooling water.

As a result, the throttle body 13 is not heated more than necessary, the volume expansion of the intake air is suppressed, and a decrease in the charging efficiency is prevented.

In this case, the temperature-sensitive responsive spring 17 is
a, the temperature of the cooling water in the hot water chamber 13a can be sensitively sensed, and supply of the cooling water,
The responsiveness of the shutoff is improved, and the supply of the cooling water temperature to the throttle body 13 is appropriately controlled, and the constant temperature state can be maintained.

Further, when the valve portion 16b performs a valve closing operation, the outer periphery of the valve portion 16b is closed by the seal ring 18, and cooling water is confined in the valve chamber 15d between the seal ring 18 and the seat surface 15e. Therefore, the trapped cooling water functions as a damper, so that the tapping sound at the time of closing the valve is eliminated and the pulsation is attenuated.

When the temperature of the cooling water drops and becomes lower than the transformation temperature of the temperature-sensitive responsive spring 17, the urging force of the temperature-sensitive responsive spring 17 is attenuated, and the valve body 16 and the seal ring 18 recede due to the cooling water pressure. The space between the surface 15e and the valve portion 16b is opened again to supply the hot water to the hot water chamber 13a of the throttle body 13. At this time, the seal ring 18 is hooked on the stepped portion 15f to stop the retreat operation, and the valve body 16 has the rear end of the valve chamber 1.
Hanging on the bottom surface of 5d, the retreat operation is stopped.

As described above, according to the present embodiment, the temperature-sensitive responsive spring 17 is arranged near the hot water chamber 13a of the throttle body 13 and is brought into direct contact with the cooling water. The temperature change of the throttle body 13 itself can be sensitively sensed, the supply and cutoff of the cooling water can be finely controlled, and the throttle body 13 can be maintained at a constant temperature.

FIGS. 7 to 10 show a second embodiment of the present invention. Cooling water control valve 14B according to the present embodiment
Has a hemispherical valve portion 16b and a similar seating surface 15e for receiving the valve portion 16b.
Even when 6 is in contact with seat surface 15e in an inclined state, the space between valve portion 16b and seat surface 15e can be sealed. The operation of the temperature sensitive spring 17 is the same as that of the first embodiment.

In this embodiment, the seal ring 18 is eliminated, and the end face of the temperature-sensitive responsive spring 17 is directly in contact with the guide rib 16c formed at the bottom of the valve portion 16b. Hooked on the step 15f,
The retreat operation is stopped (see FIG. 8).

FIGS. 11 to 14 show a third embodiment of the present invention. Cooling water control valve 14 according to the present embodiment
C is such that the valve portion 16b of the valve body 16 has a conical shape,
A circumferential guide portion 16e is provided in the middle of the spoke portion 16d formed on the outer periphery of the valve, and a temperature-sensitive responsive spring 17 is interposed between the bottom surface of the circumferential guide portion 16e and the bottom portion of the valve chamber 15d.
A return spring 20 is interposed between the upper surface of the circumferential guide 16e and the upper part of the valve chamber 15d.

In such a configuration, when the temperature of the cooling water is high and the temperature-sensitive responsive spring 17 becomes higher than the transformation temperature, the temperature-sensitive responsive spring 17 resiliently operates, and the valve body 16 is moved through the circumferential guide portion 16e. The valve closing operation is performed against the urging force of the return spring 20 (the state shown in FIG. 13). When the temperature of the cooling water drops and becomes lower than the transformation temperature of the temperature-sensitive responsive spring 17, the urging force of the temperature-sensitive responsive spring 17 is attenuated, and the valve body 16 acts as a joint between the cooling water pressure and the urging force of the return spring 20. And the valve is opened.

At this time, the peripheral edge of the circumferential guide portion 19 of the valve body 16 is hooked on the step portion 15f, and the retreat operation is stopped. In addition, a communication hole 21 for guiding cooling water having the same shape as the gap between the spoke portions 16d is formed in the circumferential guide portion 19 (see FIG. 4).

As described above, in the present embodiment, the valve opening operation of the valve element 16 is assisted by the return spring 20, so that the responsiveness is further improved.

FIGS. 15 to 20 show a fourth embodiment of the present invention. Cooling water control valve 14 according to the present embodiment
D forms a valve body 25 in a rocket shape and has a valve portion 25 at the tip end.
a is formed in a conical shape, and a circumferential guide portion 2
5b.

The valve body 25 is connected to the valve chamber 15 of the valve body 15.
d, the circumferential guide portion 25b and the valve chamber 15d.
The return spring 20 is interposed between the upper part of the spring and the upper part of the spring. Also, a spring storage recess 25 is provided in the shaft portion 25c of the valve body 25.
d is formed, and a communication hole 25e communicating with the spring accommodating recess 25d is formed in the shaft periphery of the shaft portion 25c.

Further, a temperature-sensitive responsive spring 17 is interposed between the spring housing recess 25d and the bottom of the cooling water discharge port 15c. Further, a water passage hole 28 communicating with the hot water chamber 13a of the throttle body 13 is formed around the axis of the cooling water discharge port 15c.

On the other hand, as shown in FIG. 18, a leak groove 29 is formed in the surface of the valve portion 25a in a cross shape along an inclined surface.

In such a configuration, when the temperature of the cooling water is high and the temperature-sensitive responsive spring 17 becomes higher than the transformation temperature, the temperature-sensitive responsive spring 17 resiliently operates, and the valve body 25 resists the urging force of the return spring 20. Then, the valve portion 25a is brought into close contact with the seat surface 15e formed at the discharge port of the cooling water inlet 15b of the valve main body 15.

At this time, the leak groove 2 is formed on the surface of the valve portion 25a.
9 is formed, a small amount of cooling water that does not affect the temperature rise even if it is supplied to the throttle body 13 side,
It leaks to the hot water chamber 13a through the leak groove 29.

The temperature of the cooling water leaked to the hot water chamber 13a comes into contact with the temperature-sensitive spring 17 when passing through the valve chamber 15d. The body 25 is opened and closed with high responsiveness, and the temperature of the cooling water in the hot water chamber 13a is maintained at a constant temperature.

The cooling water outlet 15c is provided with a water hole 2 around its axis.
8, the temperature-sensitive responsive spring 17 can be brought into direct contact with the cooling water in the hot water chamber 13a to detect the temperature change sensitively. , It is possible to perform more detailed control.

In this case, as shown in FIGS. 19 and 20, instead of the leak groove 29, a leak hole 30 communicating with the spring housing recess 25d is formed in the surface of the valve portion 25a. The same operation and effect can be obtained.

FIGS. 21 and 22 show a fifth embodiment of the present invention. Cooling water control valve 14 according to the present embodiment
E is a hot water chamber 1 projecting from the throttle body 13.
Nipple 31 and sub-bypass line 12 communicating with 3a
(See FIG. 1), which is provided integrally with a so-called quick connector 32.

A leak groove 33 is formed in a seat surface 15e provided at the discharge port of the cooling water inlet 15b.
The nipple 31 is inserted into the spring storage recess 25d formed in
The tip of is facing.

A protrusion 31a is formed on the outer periphery of the nipple 31, and the quick connector 32 has a protrusion 31a.
a is provided with a hook 32a which can be freely engaged and separated.

In such a configuration, the quick connector 3
2 is a nipple 3 protruding from the throttle body 13
1 and the hook 32a is engaged with a protruding ring portion 31a formed around the axis of the nipple 31, the nipple 31
Spring recess 25 formed at the tip of valve body 25
d, and a temperature-sensitive responsive spring 17 is provided on the outer periphery thereof.

As a result, the temperature-responsive spring 17 is disposed at a position close to the nipple 31 that transmits the heat of the throttle body 13, so that the temperature of the throttle body 13 can be sensitively sensed, and The supply and cutoff of the cooling water can be controlled sensitively to the temperature change of the body 13.

[0057]

As described above, according to the present invention,
The temperature sensitive spring is made to directly contact the temperature of the cooling water supplied to the part to be heated so that the temperature can be sensed. By performing the opening / closing operation with good responsiveness, the portion to be heated can be maintained at a constant temperature.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an engine cooling system according to a first embodiment.

FIG. 2 is a sectional perspective view of the cooling water control valve.

FIG. 3 is a sectional view of the cooling water control valve when the valve is opened.

FIG. 4 is a sectional view of the cooling water control valve when the valve is closed.

FIG. 5 is a sectional view taken along line VV of FIG. 3;

FIG. 6 is a sectional view taken along line VI-VI of FIG. 3;

FIG. 7 is a sectional perspective view of a cooling water control valve according to a second embodiment.

FIG. 8 is a sectional view of the cooling water control valve when the valve is opened.

FIG. 9 is a sectional view of the cooling water control valve when the valve is closed.

FIG. 10 is a sectional view taken along line XX of FIG. 8;

FIG. 11 is a sectional perspective view of a cooling water control valve according to a third embodiment.

FIG. 12 is a sectional view of the cooling water control valve when the valve is opened.

FIG. 13 is a sectional view of the cooling water control valve when the valve is closed.

14 is a sectional view taken along the line XIV-XIV in FIG.

FIG. 15 is a sectional view of a cooling water control valve according to a fourth embodiment of the present invention.

FIG. 16 is a cross-sectional view taken along the line XVI-XVI of FIG.

17 is a sectional view taken along the line XVII-XVII in FIG.

FIG. 18 is a front view of the valve element.

FIG. 19 is a sectional view of a valve element according to another embodiment of the present invention.

FIG. 20 is a front view of FIG. 19;

FIG. 21 is a side view of a quick connector according to a fifth embodiment of the present invention.

FIG. 22 is a sectional view taken along the line XXII-XXII of FIG. 21;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Engine main body 14A, 14B, 14C, 14D, 14E Cooling water control valve 15 Valve main body 15b Cooling water inflow port 15c Cooling water discharge port 15d Valve chamber 16, 25 Valve body 16a, 25c Shaft part 16b, 25a Valve part 16d Spoke part 16c Guide rib 17 Temperature-sensitive responsive spring 18 Seal ring (ring member) 19, 25b Circular guide portion 25e Communication hole

Claims (3)

[Claims] 1. A cooling water control valve for an engine through which cooling water for an engine flows when the temperature is low and shuts off when the temperature is high, wherein a cooling water inlet and a cooling water discharge port are provided at both ends of the valve body. A valve chamber is provided between an inlet and the cooling water discharge port, and a valve body that closes by moving against the water pressure from the cooling water inflow port is provided in the valve chamber. A cooling water control valve for an engine, wherein a temperature-sensitive responsive spring for closing the valve body is provided in series. 2. The valve body according to claim 1, wherein the valve body includes a shaft extending along a direction in which the cooling water flows, a valve provided at a tip of the shaft, and a spoke provided radially on an outer periphery of the shaft. A guide member radially provided on an outer periphery of the valve portion, a ring member is slidably disposed on an outer periphery of the spoke portion, and the temperature-sensitive responsive member is provided between the ring member and a bottom portion of the valve chamber. The cooling water control valve for an engine according to claim 1, wherein a spring is interposed. 3. The valve body includes a shaft extending along a direction in which the cooling water flows, a valve provided at a tip of the shaft, and a spoke radially provided on an outer periphery of the shaft. A circumferential guide portion provided on an outer periphery of the spoke portion, a communication hole is formed between the circumferential guide portion and the shaft portion, and a circumferential guide portion and a bottom portion of the valve chamber. 2. The cooling water control valve for an engine according to claim 1, wherein the temperature-responsive spring is interposed between the control valves.